Continuous chain caster and method

ABSTRACT

A continuous chain caster has upper and lower mold assemblies comprising endless belts and chains traveling at synchronized speeds. The mold assemblies meet to form a mold channel which is filled with molten metal from a headbox and feed tip. As the molten metal passes through the mold channel, the metal solidifies into the shape of the mold channel. Each belt is positioned outside the corresponding chain so that the smooth surface of the belt defines the surface of the mold channel thereby preventing the formation of fins between mold blocks which make up the chain, protecting the chain blocks, and neutralizing deformations in the chain blocks. The upper and lower blocks of the chains have protrusions at opposite ends which engage the opposing blocks to form the sides of the mold channel. By sliding the chains relative to each other, the width of the mold channel is adjustable. Further, the gauge of the mold channel is adjustable over the length of the channel by tilting one mold assembly relative to the other, so that the gauge at one end of the caster is greater than at the other end of the caster. In this embodiment, the protrusions are replaced with retractable legs which are held against the opposing block with a resilient member. The legs move in and out of slots in the blocks as the gauge of the channel mold is decreased and increased respectively.

PRIORITY CLAIM

The current application claims priority from provisional applicationSer. No. 60/006,689 filed Nov. 14, 1995.

BACKGROUND OF THE INVENTION

This invention relates to continuous casting apparatuses and methods.

Continuous casting of metals and metal alloys of various kinds, bothferrous and nonferrous, has been undertaken for many years. The majorityof the prior art discloses machines in which casting is performed bydischarging molten metal between a pair of rollers which are continuallycooled. It is possible to cast vertically downward, downward at anangle, or horizontally.

Continuous casting of metals is undertaken by two common methods thatare similar in some respects. Briefly, continuous casting is performedby means of endless members e.g. mold blocks mounted on or formingcontinuous chains, or endless belts with moving side dams disposedbetween the belts. The endless members which are typically disposedhorizontally or slanted at a small angle from the horizontal serve asthe mold for the cast metal, e.g., billet, slab, sheet, plate, or strip.The endless members, moving in non-circular paths, come togethertangentially in a casting region to form a casting mold channel and staytogether long enough so that the metal is solidified enough to supportitself after which the endless members separate and are carried back tothe beginning of the casting region. This method of casting has provedefficient and economical particularly in the casting of shapes such asslab, plate or strip, which may be used as the finished product, or ifdesired, the shape may be subjected to reduction rolling as it emergesfrom the horizontally disposed casting machine.

As stated, these generally horizontally disposed continuous castingmachines are predominantly of two types. The first type utilizes a pairof continuous belts which approach each other tangentially to form amovable mold therebetween. As the molten metal is introduced between thebelts, the belt is cooled. The cooling is, however, somewhatinefficient, and the thickness of the strip varies because of the lackof stiffness in the belt. To prevent variations in the thickness andshape of the strip, the molten metal must be supplied to the mold at alow pressure which effects the casting process and causes surface andshape problems as well as deficiencies in the metal structure.

To overcome the inefficiencies in cooling, thickness, and cast metalquality control, the belt is replaced with a continuous chain in thesecond type of caster which has consecutive mold blocks attached to oractually forming the chain. The mold blocks provide a structure whichcan be externally cooled, internally cooled, or both externally andinternally cooled. This structure efficiently cools the metal beingmolded between the caster blocks, and the continuous caster utilizingthe mold blocks also provides increased stiffness which results in auniform thickness of the strip. This process is, however, subject toother deficiencies. Where the consecutive mold blocks abut each other,molten metal can flow in between the blocks and solidify there creatingprotrusions extending from the molded metal across its width. Theseprotrusions are commonly referred to as fins. The presence of fins onthe molded strip interferes with the subsequent formation processes,such as rolling, to which the molded metal might be subjected.

Further, it is frequently necessary, during the casting of flat productssuch as sheets or strips, to adjust the width of the strip. To adjustthe width of the strip, different widths of chains must be kept in stockor continuous, expensive, adjustable width side dams which are movableacross the width of the blocks must be provided. Because of the weightand bulk of the chain, the change is a difficult, time consuming, andextremely costly procedure.

It has also been difficult to obtain high accuracies of stripthickness/shape with the continuous casting machines. As the moltenmetal moves along the length of the chain caster, the metal cools andsolidifies in the mold channel. As the metal cools, the volume decreasesthus changing the casting pressure applied to the metal as it solidifiesin the mold channel. The metal may even lose contact with the moldchannel. This slows cooling thus requiring a longer mold channel, andunder some circumstances, this can lead to undesirable variations inthickness and other shape deformations. More frequently, this hasadverse effects on the microstructure of the cast product.

Thus, the production of continuous cast products without fins isdesirable to enhance the products fabricated from continuous castingprocess and increase the ability to subject the continuously cast metalto further processing. It is also desirable to change the mold width ofa continuous caster utilizing a chain without changing the chain.Further, it is desirable to maintain the casting pressure on the metalas it solidifies. The production of continuous cast products withoutfins, shortening the stop time of a width change, changing the moldwidth without changing the chain, and controlling the casting pressure,translate directly into increased use of continuously cast products anda reduction of manufacturing expenses for continuously cast products.

BRIEF SUMMARY OF THE INVENTION

There is, therefore, provided in the practice of this invention a novelcontinuous caster comprising a headbox and a mold channel definedbetween two endless chain assemblies. The headbox is positioned at anopening of the mold channel, and molten metal is fed through the headboxto the mold channel. Each chain of the two endless chain assemblies hasa protrusion at an opposite side of the chains defining a width anddepth of the mold channel. At least one of the endless chain assembliesis movable relative to the other chain assembly, so that the width ofthe mold channel can be adjusted.

In a preferred embodiment, both of the chain assemblies are movable withrespect to each other, so that the metal being cast is maintainedcentrally in the chain caster when the width of the mold channel isadjusted. In the preferred embodiment, the caster further comprises twoendless belt assemblies which correspond to the chain assemblies. Eachbelt assembly operates externally from the corresponding chain assemblyto create a smooth mold channel which produces a casted product withoutfins. The belts can have the same width as the mold channel whichrequires the casting process to be stopped so that the belts can bechanged and the width of the mold channel changed. The relatively lightand easily removable belts can be changed in a substantially shorterperiod of time than the chains. The belts can also have a width greaterthan the width of the mold channel to adjust the width of the moldchannel without changing the belt.

The invention is further directed to a novel continuous castercomprising first and second mold assemblies having first and secondmoving chains and belts moving in first and second closed chain and beltpaths, respectively. The chain paths are internal relative to the beltpaths and the corresponding belt and chain paths join over at least thepart of their paths where the first and second paths pass in closeproximity to define a mold channel. Because the belt operates externallyfrom the chain, the smooth belt defines the surface of the mold channeland prevents finning. A headbox and tip are provided at the opening ofthe mold channel to supply molten metal to the mold channel.

In a preferred embodiment, the caster further comprises a tensioningmechanism attached to the belts whereby the belts are tightened and heldtightly against the chain. The belts are preferably coated with a heatresistant material which acts as a mold release, non-wetting agent, andheat transfer moderator. Further, cooling systems are provided for eachmold assembly. Each cooling system is associated with both the belt andchain of the respective mold assembly thereby reducing the amount ofcooling required.

The invention is still further directed to a novel continuous castercomprising a plurality of mold assemblies. At least one of the moldassemblies comprises an endless chain having a plurality of mold blocks,an upstream drive pulley, and a downstream drag pulley. The drive pulleypushes the chain into the casting region and the drag pulley tends toprevent the chain from leaving the casting region. Thus, the chain iscompressed in the casting region, and the mold blocks are pushedtogether so that there are no gaps between the mold blocks. Preferablytwo mold assemblies utilize this feature, and the drive coupled to theupstream pulley supplies at least 4 kW more power than the drag drivefor a strip 1000 mm wide and 25 mm thick. The mold blocks in thisembodiment preferably have interlocking tongue-in-groove features toprevent “roof tiling.”

In another embodiment, the invention is directed to a continuous castercomprising a headbox, a tip, and two opposing mold assemblies defining amold channel therebetween. The headbox is positioned at an opening ofthe mold channel and molten metal is fed to the mold channel through theheadbox and tip. The molten metal flows through the length of the moldchannel to an exit. A means for adjusting the depth of the mold channelalong the length of the mold channel is provided so that a depth of themold channel at the exit can be changed relative to a depth of the moldchannel at the opening during operation of the caster. To allow thedepth adjustment without stopping the casting operation, mold blocks ofthe mold assemblies define at least one slot located near an end of theblock. A leg is slidably received in the slot, and a biasing member isinterposed between a base of the slot and the leg to bias the legagainst an opposing surface.

In a preferred embodiment, each mold assembly comprises mold blocksdefining slots with legs slidably received in the slots, and biasingmembers interposed between the legs and the bases of the slots. In thisarrangement the slots of each mold assembly are on the same sideopposite the slots of the other mold assembly. The mold blocks are alsoprovided with back up extensions adjacent to the slots and locatedoutside the legs. The back up extensions engage the legs and supportthem against the outward pressure of the metal inside the mold channel.

The invention is still further directed to a novel method for changingthe width of a cast product being cast in a continuous casting processon a chain caster having two mold assemblies forming a mold channeltherebetween. An alloy is continuously melted and introduced into themold channel with a headbox through a tip. The width of the cast productis adjusted by sliding at least one of the mold assemblies relative tothe other in a direction substantially transverse to the direction oftravel of the metal through the mold channel. In a preferred embodiment,the width of the mold channel is adjusted by sliding both moldassemblies equal distances relative to each other in opposite directionswhich are substantially transverse to the direction of travel of themetal alloy, so that the alloy remains centered in the chain caster.Further, belts are used to define at least a portion of the moldchannel. If the width of the belts is the same as the mold channel, thecasting operation must be temporarily stopped and the belts and tipschanged in order to adjust the width of the cast product. If the widthof the belt is greater than the mold channel, the width of the castproduct may be adjusted by temporarily stopping the process and changingthe tip only.

The invention is still further directed to a novel method for continuouscasting of products without fins on a chain caster having two belt andchain assemblies forming a mold channel therebetween. The methodcomprises melting a metal alloy, and introducing the metal into the moldchannel. Endless belts are translated through closed paths, and endlesschains are translated through closed paths inside the belt paths. In apreferred embodiment, the method further comprises tensioning the beltsto insure that the belts do not separate from the chains in the castingregion.

Another novel method is provided according to the present invention forcompensating for volumetric changes of a metal alloy to preventundesirable deformation, abnormalities in the microstructure, andenhance cooling as the metal alloy shrinks from cooling during acontinuous casting process on a chain caster having upper and lower moldassemblies defining a mold channel therebetween. The volumetric changesare compensated for by adjusting the depth of the mold channelthroughout its length. This is accomplished by pressing a plurality ofslidable upper and lower legs held in slots of the mold blocks againstopposing mold blocks of the other assembly. The legs of the upperassembly are on opposite sides of the lower assembly. This is furtheraccomplished by tilting one of the mold assemblies relative to the otherto adjust the depth of the mold channel. Preferably, one of the moldassemblies is tilted relative to the other mold assembly to decrease thedepth of the mold channel at the exit thereby compressing the resilientmembers near the exit of the chain caster.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages of the present invention will beappreciated as the same become better understood by reference to thefollowing Detailed Description when considered in connection with theaccompanying drawings wherein:

FIG. 1 is a side view of a continuous chain caster according to thepresent invention;

FIG. 2 is a cross section of a pair of opposing mold blocks and beltstaken from inside the caster of FIG. 1;

FIG. 3 is an alternate embodiment of the opposing mold blocks and beltsof FIG. 2;

FIG. 4 is a partial side view of an inclined continuous chain casterhaving a mold channel decreasing in depth toward the exit of the chaincaster;

FIG. 5 is an end view of a pair of opposing mold blocks taken along line5—5 of the chain caster in FIG. 4; and

FIG. 6 is a side view of mold blocks having interlocking mechanismstherebetween.

DETAILED DESCRIPTION

The continuous caster shown in FIG. 1 comprises an upper mold assembly,generally designated 10, which includes an upper endless belt 12 and anupper endless chain 14 which travel in upper closed belt and chain pathsat synchronized speeds. The endless belt is formed from a strip of metalthat is cut to length and welded end to end. Thus, the mold assembly forthe preferred embodiment can also be referred to as an endless belt andchain assembly. A lower mold assembly, generally designated 16, includesa lower endless belt 18 and a lower endless chain 20 traveling in lowerclosed belt and chain paths. The two mold assemblies meet and movegenerally parallel to each other in the casting region to form arectangular mold channel 22 in between the mold assemblies, and aheadbox 24 is positioned at an opening 26 of the feed end of thecontinuous caster. The belts extend across the entire width of the moldchannel. The headbox continuously introduces molten metal to the moldchannel through a tip 27 and controls the pressure at which the metal issupplied to the mold channel. Because the belts and chains move in thedirection of arrows 30, individual mold blocks 32 and the belts of themold assemblies forming the mold channel move away from the headbox inthe direction of arrow 31 carrying metal with them, and thus, the moldassemblies continuously introduce an empty mold channel to the tip.Molten metal from the headbox continuously fills the empty portion ofthe mold channel and thus, produces a continuous molded metal 25. As themetal passes through the mold channel, it is cooled and solidified, andthe metal eventually exits the mold channel as a solid. The molded metalis preferable fed to a device 33, shown schematically, which pushes themolded metal toward the caster as it exits the mold channel to preventstrip shrinking and breakage, or the device 33 tensions the molded metalas it exits the caster. The molded metal may then be directed to othermachines for further processing.

In the preferred embodiment shown, the upper and lower chains movearound closed chain paths 34, 35 respectively defined by an upper set ofchain pulleys (sprockets) 36 and a lower set of chain pulleys(sprockets) 38, and the upper and lower belts move in closed belt paths40, 41 around a second set of upper belt pulleys 42 and a second set oflower belt pulleys 44. Over at least part of the paths, the chain andbelt paths are joined. Where the belt and chain paths join, the chainsguide and support the belts. As the two chains rotate around thepulleys, they are brought into close proximity to each other at theplace where the belt and chain paths coincide to define the shape of themold channel therebetween.

Because the belt path is the outer path relative to the chain and theinner paths relative to the mold channel, the belts define the inner,upper and lower surfaces of the mold channel, and the length of thecasting region is the length of the mold channel less the length of thetip extending into the mold channel. Therefore, the molten metalintroduced into the mold channel is formed into a strip or plate with anupper and lower surface defined by the belt, and the molten metal cannotflow into the cracks between the individual mold blocks that make up thechain. Thus, there are no fins on the molded metal 25, and the top andbottom surfaces of the molded metal, i.e. a strip or plate, are smooth.Consistent with this function, the steel belts are preferably coatedwith a heat resistant material which acts as a mold release, anon-wetting agent, and a heat transfer moderator. Further, the belts canbe added to side dams to prevent finning along the edges of the moldedmetal.

The mold blocks are cooled by internal means, external means 48 such asa water to air heat exchanger (shown schematically), or both internaland external means. The internal means comprises supply holes 49 andreturn holes 51 which form a path for a fluid to flow through the moldblock thereby cooling the mold block. Fluid manifolds, not shown, areconnected to each mold block to connect the mold blocks to a fluidreservoir. The cooling of the mold blocks solidifies the metal insidethe mold channel before it exits the caster. As shown in phantom lines,the belts can follow alternate belt paths 40′ in which the belts areexternally cooled by the same cooling mechanism 48 which externallycools the chain.

Because stiffness is provided by the chain in the present invention, thehydrostatic pressure in the headbox can be increased to increase theproduction rate of the continuous caster while still obtaining uniformthickness and a high quality molded metal. Utilizing the belt inaddition to the chain, provides the advantage of a smooth surfacewithout fins without sacrificing the advantages of using a chain. Toensure that the belt does not create variations in thickness, the beltsare held in tension with a tensioning mechanism 50 (shownschematically).

Further, the belt protects the chain, drastically reducing chain blockwear. Previously, it was necessary to periodically grind the chainblocks to maintain the desired finish on the molded metal. Eventuallythe blocks could not be ground any further and it was necessary toreplace the extremely expensive chain. Now the far less expensive beltis replaced. Thus, the combined belt and chain caster provides asubstantial cost savings by increasing chain life and reducing operatingcosts. Still further increases in metal quality occur because the beltscover the chain blocks. Specifically, the chain blocks are threedimensionally distorted when in contact with the heated metal, and thebelts which cover the chains smooth or neutralize these smalldeformations in the chain blocks so that they do not lower the qualityof the molded metal.

Referring to FIG. 2, which is a cross section of the caster of FIG. 1taken from inside the mold channel, each mold block is generallyL-shaped. The upper mold block 52 has a vertical protrusion or side dam54 with a flat and vertical inner wall extending toward the lower moldblock 56, and the lower mold block has a vertical protrusion or side dam58 with a flat and vertical inner wall extending toward the upper moldblock to form the sides of the mold channel. The protrusions arepositioned at a distance from the center of the chains toward the sidesof the mold assemblies. The protrusions engage the opposing mold block.Though in the preferred embodiment shown, the protrusions are atopposite sides of the respective mold blocks, the protrusions can belocated and spaced apart any where along the widths of the blocks.Because the protrusions engage the opposing mold block, the protrusionsdefine the width of the mold channel. The belts 60, 62 are the samewidth as the mold channel, and as described above, the belts 60, 62 formthe surfaces of the molded metal 25. To adjust the width of the moldedmetal in the embodiment of FIG. 2, the casting process must be stopped,and the belts and the tip must be changed. Belts having a width to suitthe new width of the mold channel are placed onto the chains. To changethe belts and tips, requires a short pause in the casting process.Because the belts are lighter and easier to handle than the chains, thetime required to change the belts is much shorter than the timenecessary to change the chains. After the belts are changed, at leastone of the mold assemblies is slid relative to the other, as illustratedby arrow 63, to increase or decrease the width of the mold channelbetween the protrusions of the mold blocks. The direction in which themold assemblies are slid is substantially transverse to the direction oftravel of the metal alloy through the chain caster. That is, theassembly is moved perpendicular to the direction of travel of arrow 31(FIG. 1). Because only the belts, and not the chains, are changed, thereis a significant reduction in the time the caster is not operating dueto the width change. Thus, replacing only the belts and tipssubstantially reduces the operating costs.

Utilizing the embodiment shown in FIG. 3 to change the width of themolded metal, allows width adjustments without changing the belts.Again, each mold block is generally L-shaped. The upper mold block 64has a protrusion 66 extending toward the lower mold block 68, and thelower mold block has a protrusion 70 extending toward the upper moldblock. In this embodiment, the belts 74, 76 extend beyond the moldchannel, so that the protrusions 66, 70 actually engage the beltsinstead of the opposing mold blocks. Therefore, stopping the castingprocess only to change the tip, one of the mold assemblies can be slidrelative to the other as illustrated by arrow 72 to adjust the width ofthe molded metal. This embodiment is thus capable of adjusting the widthof the mold channel without changing the belts.

In both the preferred embodiments of FIGS. 2 and 3 the width can beadjusted by moving either one of the mold assemblies or both. It ispreferred that both of the mold assemblies be moved an equal distance.When the width is adjusted by moving both the mold assemblies, themolded metal stays centered in the caster. It is important that themolded metal stay centered if it is fed to other equipment for furtherprocessing. If both the mold assemblies are moved, they are moved inopposite directions transverse, preferably perpendicular to thedirection of the metal alloy moving through the caster. It may also bepreferred in some applications to have another set of belts which wouldcover the inner sides 78 of the protrusions to prevent finning on theedges of the cast product. These methods and apparatuses provide simpleand cost effective means for width adjustment and allow use of springmounted side dams to be discussed below.

When casting widths with the preferred embodiment of the caster shown inFIG. 3, the width of the belts are frequently larger than the width ofthe molded metal. When this occurs, as shown in FIG. 3, the entirewidths of the belts are not in contact with the molten metal. This canresult in thermal distortions in the belt. Any thermal distortions whichoccur can lead to variations in the thickness of the molded metal causedby ripples in the belts. To address this problem, the belt is preferablymanufactured from a low thermal expansion material such as a high nickelalloy, stainless steel, or INVAR®. Further, the portions of the beltsnot exposed to the hot metal can be heated to prevent thermaldistortion.

Referring again to FIG. 1, as an alternative to or in conjunction withusing belts in combination with chains to prevent finning, the chainscan be pushed through the chain path in the casting region rather thanpulled through the chain path. Each of the upper 36 and lower 38 sets ofchain pulleys (sprockets) is rotationally manipulated so that the chainis compressed in the casting region. Discussing the lower assembly todescribe this arrangement, the upstream drive pulley 84 is rotated by adrive mechanism (not shown) in the direction of arrow 86, so that thechain is pushed into the casting region. Preferably the down stream dragpulley 88 has a drag generator to hinder (brake) rotation. Braking thedown stream pulley imparts a rotational force to the chain in thedirection of arrow 90. This tends to prevent the chain from exiting thecasting region. Thus, the chain is compressed and the mold blocks arepushed together in the casting region between the upstream anddownstream pulleys. In this embodiment, a gap that could allow metal toflow therein and create a fin, which would normally occur at theintersection 92 between two adjacent mold blocks 94, 96, is forcedclosed by the compression force created between the driven upstreampulley and the braked downstream drag pulley.

The drive coupled to the upstream pulley is more powerful than the dragdrive. For example, a 1000 mm wide 25 mm thick strip requiresapproximately 4 kW to convey the metal through the caster. Thus, a 2 kWdrag drive on the downstream pulley would require a 6 kW drive on theupstream pulley. In another example, a single 5.5 kW drive is used todrive the upstream pulley for both chains and a single 1.1 kW drag driveis used on each downstream pulley. This allows independent adjustment ofthe drag drives for each chain.

When a compressive forces is applied to the chain, it is preferred thatadjacent mold blocks are interlocked by a tapered key way, generallydesignated 130, and shown in FIG. 6. Each mold block 128 has a tongue132 on one side which is preferably trapezoidal in shape and a groove134 on the opposite side which is also trapezoidal in shape. The tongueand groove interlock with a corresponding groove and correspondingtongue, respectively, formed on adjacent blocks. The tapered trapezoidalshapes allow the tongue-in-groove arrangement to interlock as the blocksare translated into the mold channel. Interlocking the mold blocksprevents a problem best described as “roof tiling.” Roof tiling occurswhen the mold blocks slant in the mold channel, so that the adjacentmold edges of the mold blocks do not align. Thus, a means forinterlocking the mold blocks it provided to assure mold block edge 136alignment as shown in FIG. 6.

Referring to the preferred embodiment shown in FIG. 4, the mold channel100 of the chain caster has a depth “D” which changes along the lengthof the caster. The depth or thickness of the mold channel, more commonlyreferred to as gauge, is adjusted along the length of the caster bytilting one or both of the mold assemblies 10,16 relative to the other,so that the planes of the upper and lower belts or chains wouldeventually intersect if extended beyond the mold channel away from theexit end of the machine. Thus, the chains converge toward the exit ofthe caster. This adjustable relationship between the assemblies isobtained by a means for adjusting the depth of the mold channelcomprising a hydraulic, electromechanical, or manually adjustablecontrol mechanism, not shown, which raises or lowers one of the pulleysof an assembly relative to the other pulley of the same assembly therebychanging the angle of the assembly with respect to a stationaryreference point and with respect to the other assembly. The manualadjustment comprises a rotating adjustment screw. Preferably, theadjustment results in an opening depth 26 greater than the exit depth102 of the mold channel. Thus, the depth of the mold channel decreasesas the metal moves closer to the exit of the mold channel.

This arrangement provides control of the casting pressure through outthe mold channel as the metal decreases in volume due to cooling. As themetal cools and the volume decreases, the depth of the mold channel alsodecreases to maintain the casting pressure on the metal and preventabnormalities in microstructure, undesired deformations, and enhancecooling by maintaining contact between the metal and the belts orchains. Thus, the tolerances obtainable by the continuous castingprocess are increased, and the caster does not need to be as long. Theability to control and maintain uniform casting pressures along thelength of the chain is achieved by two features. 1) As stated, bytilting the upper chain relative to the lower, and 2) by applying aconstant force, using an air cylinder 120, spring, or other forceapplication means, to the upper chain supports which would tend to“squeeze” the chains together. This could be a passive (preset)adjustment, or it could be a continually adjustable (active control)setting which would change as process variables change.

It is also desired for some applications to cast at an angle downward.To that end the mold channel is given an angle a with the horizontal.The angle α can range from zero to ninety degrees but is preferablybetween five and fifteen degrees. Generally, the thinner the cast metal,the larger the angle α.

When the width adjustment feature of the present invention is utilizedwith the gauge adjustment feature just discussed, the preferredembodiment of the chain assembly shown in FIG. 5 is utilized. An upperblock 104 and lower block 106 are similarly constructed, and the netshape of each block is substantially an L-shape. Near the opposite sidesof the upper and lower blocks there are slots 108 which slidably receiveretractable legs or side dams 110 which are pressed against the opposingsurfaces 112 of the opposite blocks by schematically shown biasingmembers 114 which are interposed between the bases 116 of the slots andthe legs. The slots of each mold assembly are on the same side oppositethe slots of the other mold assembly. Each biasing member is preferablya resilient member such as a hydraulic/air cylinder or spring. Each legis movable within the slot and is biased by the resilient member againstthe opposing surface of the mold block or belt so that when the chainassemblies are tilted relative to each other and clamped together, theresilient member pushes the leg farther out or allows the leg to retractinwardly depending on the adjustment performed. Specifically, the legsretract when the depth is reduced and the legs extend farther out whenthe depth is increased.

The blocks also have a backup extensions 118 positioned adjacent to theslots and outwardly from the legs. The extensions engage the legs toprevent them from becoming skewed in the slots from the outward force ofthe metal, and therefore, the extensions maintain the shape of the edgeof the metal as it solidifies. The width adjustment feature functionssimilar to the embodiment described above. If the width adjustmentfeature is not required, the two legs could be positioned in the sameblock at opposite sides. This embodiment also preferably utilizes beltsas shown in FIGS. 2 or 3. Further, conventional mechanisms are providedto prevent the resilient member from ejecting the legs from the slotwhen they are not forced against an opposing mold block.

Thus, a continuous caster is disclosed which utilizes endless belt andchain assemblies with width and gauge adjustment which move relative toeach other to more efficiently obtain the desired molded metal at areduced cost. Further, chains of the chain assembly are compressed inthe casting region, and the chains have interlocking mold blocks. Thoughsome of the features of the invention are claimed in dependency, eachhas merit if used independently. While embodiments and applications ofthis invention have been shown and described, it would be apparent tothose skilled in the art that many more modifications are possiblewithout departing from the inventive concepts herein. For example, theseconcepts could be applied to a vertical caster. It is, therefore, to beunderstood that within the scope of the appended claims, this inventionmay be practiced otherwise than as specifically described.

What is claimed is:
 1. A continuous caster comprising: a headbox; a tip;a mold channel having a depth defined between two endless chainassemblies each having a chain; the headbox and tip being positioned atan opening to the mold channel to supply molten metal from the headboxto the mold channel; each chain having a protrusion at an opposite sideof the chains defining a width of the mold channel therebetween; a meansfor adjusting the depth of the mold channel along the length of the moldchannel so that an exit depth of the mold channel is less than anopening depth of the mold channel; and at least one of the endless chainassemblies being moveable relative to the other to adjust the width ofthe mold channel.
 2. The caster according to claim 1 further comprisingtwo endless belt assemblies each corresponding to one of the chainassemblies and wherein each belt assembly has a belt which operatesexternally of the corresponding chain assembly to create a smooth moldchannel which produces a cast product without fins.
 3. The casteraccording to claim 2 wherein the belts have widths equal to the width ofthe mold channel.
 4. The caster according to claim 2 wherein the beltshave widths greater than the width of the mold channel to adjust thewidth of the mold channel without changing the belts.
 5. The casteraccording to claim 2 further comprising a tensioning mechanism attachedto the belt to tighten and hold the belt against the chain.
 6. Thecaster according to claim 2 further comprising a coating of a heatresistant material on the belts acting as a mold release, non-wettingagent, and heat transfer moderator.
 7. The caster according to claim 2further comprising a first external means for cooling associated withone of the belts and one of the chains, and a second external means forcooling associated with the other belt and the other chain.
 8. Thecaster according to claim 1 wherein the chain assemblies are moveablewith respect to each other to adjust the width of the mold channel andto maintain the molten metal centrally in the chain caster.
 9. Thecaster according to claim 1 wherein the mold channel extends over alength between an opening and an exit, and the caster further comprises:at least one of the chain assemblies comprises a plurality of moldblocks; and each mold block comprises at least one slot positioned nearan end of the block, at least one leg slidably received in the slotdefining sides of the mold channel, and at least one biasing memberinterposed between a base of the slot and the leg to bias the legagainst an opposing surface to maintain the sides of the mold channelduring a depth adjustment.
 10. The caster according to claim 9 whereinboth chain assemblies comprise mold blocks, and the slots of each moldblock of one of the chain assemblies are on the same side opposite theslots of the mold blocks of the other chain assembly.
 11. The casteraccording to claim 9 wherein each mold block comprises a backupextension located adjacent the slot and outwardly from the leg, and theextension engaging the leg to support it.
 12. The caster according toclaim 1 wherein the depth is adjusted so that the chains converge towardan exit of the mold channel.
 13. The caster according to claim 1Acontinuous caster comprising: a headbox; a tip; a mold channel having adepth defined between two endless chain assemblies each having a chain;the headbox and tip being positioned at an opening to the mold channelto supply molten metal from the headbox to the mold channel; each chainhaving a protrusion at an opposite side of the chains defining a widthof the mold channel therebetween; a means for adjusting the depth of themold channel along the length of the mold channel so that an exit depthof the mold channel is less than an opening depth of the mold channel;and at least one of the endless chain assemblies being moveable relativeto the other to adjust the width of the mold channel; wherein at leastone of the chain assemblies comprises an endless chain having aplurality of mold blocks, an upstream drive pulley pushing the chaininto a casting region of the carts, and a downstream drag pulley havinga drag generator hindering rotation to compress the chain in the castingregion and push the mold blocks together to reduce finning.
 14. Thecaster according to claim 13 further comprising an upstream drivecoupled to the upstream drive pulley and a drag drive coupled to thedownstream drag pulley, and wherein the upstream drive is more powerfulthan the drag drive.
 15. The caster according to claim 14 wherein theupstream drive is 6 kW and the drag drive is 2 kW.
 16. The casteraccording to claim 13 wherein the mold blocks comprise interlocking moldblocks.
 17. A method for continuous casting of a cast product having awidth and a depth on a chain caster having two mold assemblies withchains forming a mold channel, the method comprising: continuouslymelting a metal alloy; continuously introducing the molten metal alloyinto the mold channel with a headbox and a tip; moving at least one ofthe mold assemblies relative to the other in a direction substantiallytransverse to a direction of travel of the metal alloy through the moldchannel to adjust any one of the width and depth of the cast product;and converging one mold assembly relative to the other mold assembly ina direction of travel of the metal alloy through the mold channel tocompensate for metal shrinkage and casting pressure regulation along thelength and width of the mold channel.
 18. The method according to claim17 further comprising sliding at least one of the mold assembliesrelative to the other to adjust the width of the cast product.
 19. Themethod according to claim 17 further comprising sliding both moldassemblies equal distances relative to each other in opposite directionssubstantially transverse to the direction of travel of the metal alloyto adjust the width of the cast product.
 20. The method according toclaim 17, wherein the mold assemblies have a belt, further comprisingchanging the belt on the mold assemblies.
 21. The method according toclaim 17, wherein the mold assemblies have an endless belt, furthercomprising: translating the endless belt of the assemblies through aclosed belt path covering the entire width of the mold channel; andtranslating the chains of the assemblies through a closed chain pathinside the closed belt path.
 22. The method according to claim 21wherein each belt defines a portion of the mold channel and has a widthgreater than a width of the mold channel, the method further comprisingheating portions of each belt not in contact with the metal alloy. 23.The method according to claim 21 further comprising tensioning eachbelt.
 24. The method according to claim 17 further comprising: tiltingat least one mold assembly relative to the other; and converging themold assemblies toward the exit of the mold channel.
 25. The methodaccording to claim 17 wherein the chains comprise mold blocks, themethod further comprising: pressing a plurality of slidable upper legsheld in slots of the mold blocks of one of the mold assemblies againstopposing mold blocks of the other mold assembly with resilient members;pressing a plurality of slidable lower legs held in slots of the moldblocks of the other mold assembly against opposing mold blocks of theone mold assembly with resilient members and at an opposite side of theone mold assembly from the upper legs; and tilting one of the moldassemblies relative to the other to adjust the depth of the moldchannel.
 26. The method according to claim 25 wherein tilting one of themold assemblies comprises tilting one of the mold assemblies to decreasethe depth of the mold channel at an exit of the mold channel andcompressing the resilient members near the exit of the mold channel. 27.The method according to claim 17 further comprising: A method forcontinuous casting of a cast product having a width and a depth on achain caster having two mold assemblies with chains forming a moldchannel the method comprising: continuously melting a metal alloy;continuously introducing the molten metal alloy into the mold channelwith a headbox and a tip; moving at least one of the mold assembliesrelative to the other in a direction substantially transverse to adirection of travel of the metal alloy through the mold channel toadjust any one of the width and depth of the cast product; convergingone mold assembly relative to the other mold assembly in a direction oftravel of the metal alloy through the mold channel to compensate formetal shrinkage and casting pressure regulation along the length andwidth of the mold channel; rotating upstream pulleys with a drive indirections such that the upstream pulleys are pushing the chains into acasting region of the chain caster; and hindering rotation of downstreampulleys with a drag generator such that the upstream pulleys and thedownstream pulleys are pressing a plurality of mold blocks connected tothe chains together in the casting region.
 28. The method according toclaim 17 27further comprising compressing the chains in the castingregion so that there are no gaps between the mold blocks of the chains.29. A continuous caster comprising: a headbox; a tip; a mold channeldefined between two endless chain assemblies each having a chain; theheadbox and tip being positioned at an opening to the mold channel tosupply molten metal from the headbox through the tip to the moldchannel; each chain having a protrusion at an opposite side of thechains defining a width of the mold channel therebetween; at least oneof the endless chain assemblies comprises a plurality of mold blocksbeing moveable relative to the other to adjust the width of the moldchannel, an upstream drive pulley pushing the chain in the mold channeland a downstream drag pulley having a drag generator hindering rotationto compress the chain in the mold channel and push the mold blockstogether to reduce finning; and each mold block comprises at least oneslot positioned near an end of the block, at least one leg slidablyreceived in the slot defining sides of the mold channel, and at leastone biasing member interposed between a base of the slot and the leg tobias the leg against an opposing surface to maintain the sides of themold channel during a depth adjustment.
 30. A method for compensatingfor volumetric changes of a metal alloy to prevent undesirabledeformation as the metal alloy cools during a continuous casting processon a chain caster having upper and lower mold assemblies forming a moldchannel extending over a length and having a depth, exit, and opening,the method comprising: pressing a plurality of slidable upper legs heldin slots of the mold blocks of the upper mold assembly against opposingmold blocks of the lower mold assembly with resilient members; pressinga plurality of slidable lower legs held in slots of the mold blocks ofthe lower mold assembly against opposing mold blocks of the upper moldassembly with resilient members and at an opposite side of the uppermold assembly from the upper legs; and tilting one of the moldassemblies relative to the other to adjust the depth of the moldchannel; rotating upstream pulleys with a drive in directions such thatthe upstream pulleys are pushing the mold assemblies into a castingregion of the chain caster; and hindering rotation of downstream pulleyswith a drag generator such that the upstream pulleys and the downstreampulleys are pressing a plurality of the mold blocks connected to themold assemblies together in the casting region.
 31. A continuous chaincaster having a casting region, the caster including: a plurality ofmold assemblies forming a mold channel therebetween; and at least onemold assembly comprising an endless chain having a plurality ofinterlocking mold blocks, an upstream drive pulley pushing the chaininto the casting region, and a downstream drag pulley having a draggenerator hindering rotation to compress the chain in the casting regionand push the mold blocks together to reduce finning.
 32. A method forcontinuous casting of products on a chain caster having a casting regionand two chain assemblies each having an upstream pulley and a downstreampulley to drive a chain comprised of a plurality of interlocking moldblocks and the chain assemblies forming a mold channel therebetween, themethod comprising: rotating the upstream pulleys with a drive indirections such that the pulleys are pushing the chains into the castingregion; and hindering rotation of the downstream pulley with a draggenerator such that the upstream pulleys and downstream pulleys arepressing the mold blocks together in the casting region.
 33. Acontinuous non-vertical caster for casting a non-ferrous metal or analloy thereof to a predetermined width and depth comprising: a headbox;a tip; two opposed endless mold assemblies that can each travel along aclosed path and that cooperate to define a mold channel between them;the mold channel having a feed opening and an exit and a casting regiontherebetween, and the metal or alloy, in a molten state, being able tomove in the mold channel in a direction of travel between the feedopening and the exit; the mold channel having a depth that is definedbetween the two opposed mold assemblies; at least one of the moldassemblies having a plurality of mold blocks; the headbox and tip beingpositioned at the feed opening to supply the metal or alloy, in themolten state, from the headbox through the tip into the mold channel; aside dam on an opposite side of each mold assembly defining respectivesides and a width of the mold channel between the side dams; adjustingmeans for changing the position of one of the endless mold assembliesrelative to the other in at least one of two orthogonal directionstransverse to the direction of travel to adjust any one of the width andthe depth of the mold channel and thereby to adjust any one of the widthand the depth of the metal or alloy in the molten state moving throughthe mold channel; and internal cooling means in the mold blocks to coolthe mold blocks to solidify the metal or alloy in the mold channel;wherein at least one of the mold assemblies further comprises anupstream drive pulley pushing the mold blocks into the casting regionand a downstream drag pulley having a drag generator hindering rotationto compress the mold assembly in the casting region and push the moldblocks together to reduce finning.
 34. The caster of claim 33 whereinexternal cooling means also cool the mold blocks to solidify the metalor alloy in the mold channel.
 35. The caster of claim 33 comprisingfirst adjusting means for changing the position of one of the endlessmold assemblies relative to the other in a first of the two orthogonaldirections to adjust the width of the mold channel.
 36. The caster ofclaim 35, wherein both mold assemblies are supported for movement at anequal distance in opposite directions with respect to each other whenadjusting the width of the mold channel so as to enable the metal to bemaintained centrally in the caster.
 37. The caster of claim 35, furthercomprising second adjusting means for changing the position of one ofthe endless mold assemblies relative to the other in a second of the twoorthogonal directions to adjust the depth of the mold channel.
 38. Thecaster of claim 37, wherein the second adjusting means can change thedepth of the mold channel lengthwise of the mold channel so that thedepth of the mold channel at the exit is less than the depth of the moldchannel at the feed opening thereby providing a convergence of the moldtoward the exit.
 39. The caster of claim 38 wherein the second adjustingmeans can change the depth of the mold channel to maintain theconvergence of the mold assemblies.
 40. The caster of claim 37 whereinwhen the second adjusting means changes the position of one of theassemblies in said second of the two orthogonal directions the extent towhich each side can dam extends from its mold assembly is adjustedautomatically.
 41. The caster of claim 40 wherein the side dam from eachmold assembly in defining the depth of the mold channel extends only tothe other mold assembly.
 42. The caster of claim 40 wherein each moldblock comprises at least one slot positioned near a side of the block,at least one side dam slidably received in the slot and defining a sideof the mold channel and at least one biasing member interposed between abase of the slot and the side dam to bias the side dam against anopposing surface to maintain the side of the mold channel during any oneof a width and a depth adjustment.
 43. The caster of claim 42 whereinthe slots of the mold blocks of one of the mold assemblies are on thesame side but are on the opposite side from the slots of the mold blocksof the other mold assembly.
 44. The caster of claim 43 wherein each moldblock comprises a backup extension located adjacent the slot andoutwardly from the side dam and the extension engages the side dam tosupport it.
 45. The caster of claim 43 wherein the side dam from eachmold assembly in defining the depth of the mold channel extends only tothe other mold assembly.
 46. The caster of claim 45 wherein a first oneof the endless mold assemblies can travel along a first closed path, asecond one of the mold assemblies can travel along a second closed pathwherein the second closed path at least in part extends in closeproximity to the first closed path and wherein the first one of the moldassemblies and the second one of the mold assemblies each have asubstantially flat surface to form a rectangular mold channel betweenthem.
 47. The caster of claim 42 wherein a first one of the endless moldassemblies can travel along a first closed path, a second one of themold assemblies can travel along a second closed path wherein the secondclosed path at least in part extends in close proximity to the firstclosed path and wherein the first one of the mold assemblies and thesecond one of the mold assemblies each have a substantially flat surfaceto form a rectangular mold channel between them.
 48. The caster of claim47 yet further comprising two endless belts each traveling around andparallel to one of the mold assemblies and each traveling between thetwo mold assemblies to provide between the endless belts a smooth moldchannel which can produce a cast product without fins in the regionscontacted by the belts.
 49. The caster of claim 48 still furthercomprising external cooling means to cool both the mold blocks and theendless belts to solidify the metal or alloy in the mold channel. 50.The caster of claim 49 wherein the external cooling means to cool boththe mold blocks and the endless belts are the same external coolingmeans.
 51. The caster of claim 49 wherein the endless belts have widthsgreater than the width of the mold channel so that the width of the moldchannel can be adjusted without changing the belts.
 52. The caster ofclaim 46 yet further comprising two endless belts each traveling aroundand parallel to one of the mold assemblies and each traveling betweenthe two mold assemblies to provide between the endless belts a smoothmold channel which can produce a cast product without fins in theregions contacted by the belts.
 53. The caster of claim 52 still furthercomprising external cooling means to cool both the mold blocks and theendless belts to solidify the metal or alloy in the mold channel. 54.The caster of claim 53 wherein the external cooling means to cool boththe mold blocks and the endless belts are the same external coolingmeans.
 55. The caster of claim 54 wherein the endless belts have widthsgreater than the width of the mold channel so that the width of the moldchannel can be adjusted without changing the belts.
 56. A method forcontinuous non-vertical casting of a non-ferrous metal or an alloythereof to a predetermined width and depth wherein two opposed endlessmold assemblies each having a plurality of mold blocks and travelingalong a closed path cooperate to define a mold channel between them; themold channel having a feed opening and an exit and a casting regiontherebetween and the metal or alloy in a molten state being able to movein the mold channel in a direction of travel between the feed openingand the exit; the method comprising the steps of: melting the metal oralloy; introducing the metal or alloy in a molten state into the feedopening; translating the mold assemblies along closed paths along thedirection of travel between them; cooling the mold blocks internally tosolidify the metal or alloy in the mold channel; moving the moldassemblies relative to one another in one of two orthogonal directionssubstantially transverse to the direction of travel to adjust any one ofthe width and the depth of the mold channel and thereby to adjust anyone of the width and the depth of the metal or alloy in the molten statemoving through the mold channel; rotating upstream pulleys with a driveand direction such that the upstream pulleys are pushing at least one ofthe mold assemblies into a casting region; and hindering rotation ofdownstream pulleys with a drag generator such that the upstream pulleysand the downstream pulleys are pressing a plurality of mold blockstogether in the casting region.
 57. The caster of claim 56 whereinexternal cooling means also cool the mold blocks to solidify the metalor alloy in the mold channel.
 58. The method of claim 56 furthercomprising a step of adjusting the width of the mold channel by slidingat least one of the mold assemblies to move it relative to the other inthe direction transverse to the direction of travel of the metal oralloy.
 59. The method of claim 58 further comprising a step of adjustingthe width of the mold channel by sliding each of the mold assemblies anequal distance in opposite directions transverse to the direction oftravel whereby the metal or alloy remains centered in the caster. 60.The method of claim 59 further comprising the step of tilting the moldassemblies relative to one another so that they converge in thedirection of travel to compensate for metal shrinkage and providecasting pressure regulation along the length and width of the moldchannel in the direction of travel.
 61. The method of claim 60 whereineach mold assembly extends as far as the other mold assembly transverseto the direction of travel and includes a projecting side dam defining aside of the mold channel; and wherein the side dam of each mold assemblyduring the step of tilting the mold assemblies relative to one anotherextends towards and is pressed against the other mold assembly.
 62. Themethod of claim 60 wherein each side dam of one of the mold assembliesis pressed against the other mold assembly by a resilient member betweenthe side dam and the one mold assembly.
 63. The method of claim 56further comprising the steps of: pressing a plurality of slidable upperside dams held in slots of the mold blocks of an upper one of the moldassemblies against the mold blocks of a lower one of the mold assemblieswith resilient members between the upper side dams and the mold blocksof the upper mold assembly; pressing a plurality of slidable lower sidedams held in slots of the mold blocks of the lower mold assembly againstthe mold blocks of the upper mold assembly with resilient membersbetween the lower side dams and the mold blocks of the lower moldassembly; the lower and upper side dams being on opposite sides of themold channel; and tilting the mold assemblies relative to one another toadjust the depth of the mold channel along the direction of travel. 64.The method of claim 63 wherein the step of tilting the mold assembliesrelative to one another decreases the depth of the mold channel at theexit of the mold channel and compresses the resilient members near theexit.
 65. The method of claim 56 further comprising the step oftranslating opposed endless belts through closed belt paths along thedirection of travel and over the width of the mold channel; the closedpath of each mold assembly being within the closed belt path of one ofthe endless belts.
 66. The method of claim 65 wherein external coolingmeans cool both the mold blocks and the endless belts to solidify themetal or alloy in the mold channel.
 67. The method of claim 66 whereinthe same external cooling means cool both the mold blocks and theendless belts.
 68. The method of claim 65 wherein a step of adjustingthe width of the mold channel includes a step of changing the width ofthe opposed endless belts.
 69. The caster of claim 13 wherein the casteris a non-vertical caster.
 70. The method of claim 27 wherein the chaincaster is a non-vertical chain caster.
 71. The caster of claim 29 wherein the caster is a non-vertical caster.
 72. The method of claim 30wherein the chain caster is a non-vertical chain caster.
 73. The methodof claim 27 wherein the case product is a non-ferrous metal or alloy.74. The method of claim 30 wherein the metal alloy is non-ferrous.